Three-dimensional shaping apparatus, three-dimensional shaping method, and information processing device

ABSTRACT

A three-dimensional shaping apparatus includes a control unit configured to control a supply unit, a leveling unit, and an ejection unit to repeat a set of processes of supplying powder, forming powder layer, and ejecting shaping liquid to shape a three-dimensional shaped object corresponding to the shaping target. The control unit is configured to stop the set of processes in response to reception of a stop signal, and in response to reception of a resume signal after the reception of the stop signal, control the supply unit, the leveling unit, and the ejection unit to eject the shaping liquid onto at least a part of a dot region on a surface of an outermost powder layer, the dot region being formed by at least one dot formed at the outermost powder layer, and then resume the set of processes.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims priority under 35 U.S.C. §119 to JapanesePatent Application No. 2015-125091 filed on Jun. 22, 2015 and JapanesePatent Application No. 2016-020140 filed on Feb. 4, 2016. The contentsof which are incorporated herein by reference in their entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a three-dimensional shaping apparatus,a three-dimensional shaping method, and an information processingdevice.

2. Description of the Related Art

Three-dimensional shaping apparatuses using the inkjet printingtechnology are known. It is known that a set of processes of supplyingpowder, leveling the surface of the powder to form a powder layer, andejecting shaping liquid to the powder layer to form dots, for example,is repeated to shape a three-dimensional shaped object. Typicaltechniques known to the inventor are described in Japanese PatentApplication Laid-open No. 2000-015613, for example.

When the apparatus stops operation in the middle of the processes andthen starts the operation again, dots formed by the shaping liquidejected to the powder layer before the stop of operation, in some cases,do not combine with dots formed by the shaping liquid ejected to a newlyformed powder layer after the resuming of the operation, which maycreate discontinuity between the dots. In this case, the resultingthree-dimensional shaped object includes a portion, which was formedbefore the stop and after the resuming of the operation, less strongthan the other portions of the three-dimensional shaped object, in somecases. In other words, typical techniques known to the inventor cannotprevent strength loss in the three-dimensional shaped object.

SUMMARY OF THE INVENTION

According to one aspect of the present invention, a three-dimensionalshaping apparatus includes: a supply unit, a leveling unit, an ejectionunit, a control unit and a reception unit. The supply unit is configuredto supply powder. The leveling unit is configured to level a surface ofthe supplied powder in a first direction to form a powder layer. Theejection unit is configured to eject shaping liquid to at least oneposition on a surface of the powder layer, the at least one positioncorresponding to a shaping target, to form at least one dot. The controlunit is configured to control the supply unit, the leveling unit, andthe ejection unit to repeat a set of processes of supplying the powder,forming the powder layer, and ejecting the shaping liquid to shape athree-dimensional shaped object corresponding to the shaping target. Thereception unit is configured to receive a stop signal indicating a stopof operation and a resume signal indicating resuming of the operation.The control unit is configured to stop the set of processes in responseto reception of the stop signal, and in response to reception of theresume signal after the reception of the stop signal, control the supplyunit, the leveling unit, and the ejection unit to eject the shapingliquid onto at least a part of a dot region on a surface of an outermostpowder layer, the dot region being formed by at least one dot formed atthe outermost powder layer, and then resume the set of processes.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view illustrating an example of athree-dimensional shaping apparatus;

FIG. 2 is a schematic view illustrating an example of the procedure of aset of processes;

FIG. 3 is a schematic view illustrating an example of the procedure forshaping a three dimensional shaped object;

FIG. 4 is a schematic view illustrating an example of a phenomenon wherediscontinuity is created between dots in powder layers;

FIG. 5 is a functional block diagram of the three-dimensional shapingapparatus;

FIG. 6 is a schematic view illustrating an example of the procedure forshaping a three dimensional shaped object;

FIG. 7 is a view illustrating a state of dots;

FIG. 8 is a view illustrating regions to which shaping liquid isejected;

FIGS. 9A and 9B are a graph and a view illustrating an example of therelation between standby time and an ejection amount;

FIGS. 10A and 10B are schematic views illustrating an example of a stateof the powder layer;

FIG. 11 is a flowchart illustrating an example of the procedure ofshaping processing;

FIG. 12 is a flowchart illustrating an example of the procedure ofinterruption processing; and

FIG. 13 is a diagram illustrating a hardware configuration of aninformation processing device.

The accompanying drawings are intended to depict exemplary embodimentsof the present invention and should not be interpreted to limit thescope thereof. Identical or similar reference numerals designateidentical or similar components throughout the various drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of the presentinvention.

As used herein, the singular forms “a”, “an” and “the” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise.

In describing preferred embodiments illustrated in the drawings,specific terminology may be employed for the sake of clarity. However,the disclosure of this patent specification is not intended to belimited to the specific terminology so selected, and it is to beunderstood that each specific element includes all technical equivalentsthat have the same function, operate in a similar manner, and achieve asimilar result.

The following describes an embodiment of a three-dimensional shapingapparatus, a three-dimensional shaping method, and an informationprocessing apparatus in detail with reference to the accompanyingdrawings.

An object of an embodiment is to reduce strength loss in athree-dimensional shaped object.

FIG. 1 is a schematic view illustrating an example of athree-dimensional shaping apparatus 10.

The apparatus 10 includes a shaping device 12, an information processingdevice 14, and a user interface (UI) unit 36. The shaping device 12 andthe UI unit 36 are connected with the information processing device 14to be able to send and receive data and signals to and from each other.

The UI unit 36 receives various operation instructions from the user anddisplays various types of information. The UI unit 36 is, for example, adisplay with a keyboard or a touch screen. The UI unit 36 may beseparated into an operating unit that receives operation instructionsfrom the user and a display unit that displays various types ofinformation.

The information processing device 14 controls the shaping device 12. Theshaping device 12 shapes a three dimensional shaped object under thecontrol of the information processing device 14. The shaping device 12includes a supply unit 18, a leveling unit 16, an ejection unit 26, ashaping unit 22, and a maintenance unit 29.

The supply unit 18 stores therein powder 20 to be supplied to theshaping unit 22. In the present embodiment, the supply unit 18 and theshaping unit 22 are disposed in series in a first direction (see thearrow X in FIG. 1), which may be hereinafter referred to as a firstdirection X. In the present embodiment, the first direction X isdescribed as one direction in the horizontal plane. In the presentembodiment, the supply unit 18 and the shaping unit 22 are disposed inseries in the first direction X with the supply unit 18 being disposedupstream and the shaping unit 22 being disposed downstream in the firstdirection X.

The supply unit 18 includes a supply chamber 18A, a stage 18C, and asupport 18B. The supply chamber 18A stores therein the powder 20. Thesupply chamber 18A opens vertically upwards (in the direction of thearrow ZA in FIG. 1). In the present embodiment, the supply chamber 18Ahas an opening having the same shape and the same opening area as anopening of a shaping chamber 22A (to be described later) of the shapingunit 22, and is disposed in series in the first direction X with respectto the shaping unit 22.

When the amount of the powder 20 stored in the supply chamber 18A isreduced to a predetermined amount or less, a separately disposed powdersupply mechanism supplies the powder 20 to the supply chamber 18A torecover the reduced amount.

The stage 18C constitutes the inner bottom of the supply chamber 18A.The stage 18C is supported by the support 18B. The support 18B movablysupports the stage 18C in a direction perpendicular to the horizontaldirection (see the double arrow Z in FIG. 1).

In the present embodiment, the support 18B moves the stage 18Cvertically upwards (see the arrow ZA in FIG. 1) by a predeterminedamount at a time under the control of the information processing device14. This operation pushes up a part of the powder 20 stored in thesupply chamber 18A above the opening of the supply chamber 18A. When thepowder supply mechanism supplies the powder to the supply chamber 18A,the support 18B moves the stage 18C vertically downwards (in thedirection of the arrow ZB in FIG. 1) under the control of theinformation processing device 14.

In the shaping unit 22, a three-dimensional shaped object is shaped. Theshaping unit 22 includes the shaping chamber 22A, a support 22B, and astage 22C.

The shaping chamber 22A stores therein the powder 20 supplied from thesupply unit 18. To the powder 20 stored in the shaping chamber 22A,shaping liquid 28 is ejected, and a three-dimensional shaped object isshaped inside the shaping chamber 22A. The shaping chamber 22A opensvertically upwards (in the direction of the arrow ZA in FIG. 1). Theopening of the shaping chamber 22A is disposed in series in the firstdirection X with respect to the opening of the supply chamber 18A.

The stage 22C constitutes the inner bottom of the shaping chamber 22A.The stage 22C is supported by the support 22B. The support 22B movablysupports the stage 22C in a direction perpendicular to the horizontaldirection (see the double arrow Z in FIG. 1).

In the present embodiment, the support 22B moves the stage 22Cvertically downwards (see the arrow ZB in FIG. 1) by a predeterminedamount at a time under the control of the information processing device14. This operation creates a space at the opening of the shaping chamber22A for receiving newly supplied powder 20 from the supply unit 18.

The leveling unit 16 is a long member extending, at the opening of thesupply chamber 18A, in a direction (Y direction in FIG. 1) perpendicularto the first direction X in which the supply unit 18 and the shapingunit 22 are disposed in series. The leveling unit 16 has, for example, ashape of a circular cylinder or a plate.

The leveling unit 16 is supported to be able to reciprocate upstream anddownstream in the first direction X. The leveling unit 16 reciprocatesupstream and downstream in the first direction X under the control ofthe information processing device 14.

The leveling unit 16 is initially disposed upstream of the supply unit18 in the first direction, and moves downstream along the firstdirection X under the control of the information processing device 14.By this operation, the powder 20 pushed up above the opening of thesupply chamber 18A is sent toward the shaping unit 22 and is supplied tothe shaping unit 22.

The leveling unit 16 moves further downstream in the first direction Xunder the control of the information processing device 14. In thisoperation, the leveling unit 16 levels the surface of the powder 20supplied to the shaping unit 22 in the first direction X, therebyforming a powder layer 24 having a thickness J in the shaping chamber22A.

After the leveling unit 16 moves from a position upstream of the supplyunit 18 to a position downstream of the shaping unit 22 in the firstdirection X and forms the powder layer 24, the leveling unit 16 movesback in the first direction X to the upstream position at which theleveling unit 16 is initially disposed.

In the context of the present embodiment, the supply unit 18 storestherein the powder 20 to be supplied to the shaping unit 22, and theleveling unit 16 moves in the first direction X to supply the powder 20stored in the supply unit 18 to the shaping unit 22 to form the powderlayer 24. In the present embodiment, however, the supply unit 18 maydirectly supply the powder 20 to the shaping unit 22, and the levelingunit 16 may level the surface of the powder 20 supplied to the shapingunit 22 to form the powder layer 24.

The ejection unit 26 ejects the shaping liquid 28 to a position on thesurface of the powder layer 24 corresponding to a shaping target, andforms a dot 30.

The ejection unit 26 includes a mechanism of a known inkjet printingtechnique. The ejection unit 26 is supported to be able to move in thefirst direction X, the direction perpendicular to the horizontaldirection (the direction of the arrow Z in FIG. 1), and the directionperpendicular to the first direction and the direction of the arrow Z(the direction of the arrow Y in FIG. 1).

The ejection unit 26 ejects the shaping liquid 28 to positions on thesurface of the powder layer 24 corresponding to a shaping target to formdots 30 under the control of the control unit 14B. Specifically, theejection unit 26 ejects droplets of the shaping liquid 28 from aplurality of nozzles to form the dots 30.

The maintenance unit 29 is a mechanism for preserving and recovering thecondition or the state of the ejection unit 26. The maintenance unit 29includes a mechanism for correcting ejection defects of the ejectionunit 26 in ejecting the shaping liquid 28. The maintenance unit 29 canbe any known maintenance mechanism typically used for inkjet heads. Forexample, the maintenance unit 29 may include a suction mechanism fordrawing the shaping liquid 28 from the nozzles of the ejection unit 26or a wiping mechanism for wiping the nozzle surface of the ejection unit26.

The information processing device 14 controls the supply unit 18, theleveling unit 16, and the ejection unit 26 to repeat a set of processesof supplying the powder 20, forming the powder layer 24, and ejectingthe shaping liquid 28 in this order to shape a three-dimensional shapedobject corresponding to a shaping target.

The powder 20 is made of a base material in a particulate form with thesurface covered with a coating layer (details will be described later).The shaping liquid 28 has a function of dissolving the coating layer andthen solidifying the coating layer (details will be described later).

By this function, at least a part of the coating layer of the powder 20is dissolved and then combined with each other in a region on the powderlayer 24 to which the shaping liquid 28 is ejected to form dots 30. Thedots 30 are then layered by the repetition of the processes of formingthe powder layer 24 and ejecting the shaping liquid 28. With thisoperation, dot regions formed by the dots 30 in powder layers 24 aresuccessively solidified, thereby forming a three-dimensional shapedobject.

FIG. 2 is a schematic view illustrating an example of the procedure ofthe set of processes of supplying the powder 20, forming the powderlayer 24, and ejecting the shaping liquid 28. The set of processesdescribed below are performed under the control of the informationprocessing device 14.

The supply unit 18 and the leveling unit 16 supply the powder 20 to theshaping unit 22, and the leveling unit 16 levels the surface of thepowder 20 in the first direction X, thereby forming, for example, afirst powder layer 24 (powder layer 24 ₁) (see (A) in FIG. 2).

The ejection unit 26 then ejects the shaping liquid 28 to a position onthe surface of the powder layer 24 ₁ corresponding to a shaping target(see (A) in FIG. 2). By this process, dots 30 are formed at the powderlayer 24 ₁ with the shaping liquid 28 (see (B) in FIG. 2).

Subsequently, the support 22B moves the stage 22C vertically downwards(in the direction of the arrow ZB) by a predetermined amount under thecontrol of the information processing device 14 (see (C) in FIG. 2).This operation creates a space at the opening of the shaping chamber 22Afor receiving newly supplied powder 20 from the supply unit 18. Thepredetermined amount may be equal to or larger than the thickness J ofthe powder layer 24 to be formed with the newly supplied powder 20.

The thickness J of the powder layer 24 may be determined such that, forexample, one droplet of the shaping liquid 28 ejected from the ejectionunit 26 permeates into the powder layer 24 in the thickness directionfrom one surface to the other surface thereof. The thickness J variesdepending on the kind of the powder 20 or the shaping liquid 28, or theejection properties of the ejection unit 26. The thickness J is, forexample, tens of μm to 100 μm.

Subsequently, the support 18B moves the stage 18C vertically upwards (inthe direction of the arrow ZA) by a predetermined amount under thecontrol of the information processing device 14. The predeterminedamount is such an amount that the powder 20 is pushed up at the openingof the supply chamber 18A in an amount sufficient to form a powder layer24 having the thickness J in the shaping unit 22. This operation pushesup a part of the powder 20 stored in the supply chamber 18A above theopening of the supply chamber 18A (see (C) in FIG. 2).

The leveling unit 16 initially disposed upstream of the supply unit 18in the first direction X moves downstream along the first direction Xunder the control of the information processing device 14. By thisoperation, the powder 20 pushed up above the opening of the supplychamber 18A is sent toward the shaping unit 22 and is supplied to theshaping unit 22 (see (C) and (D) in FIG. 2).

The leveling unit 16 moves further downstream in the first direction X.The leveling unit 16 levels the surface of the powder 20 supplied to theshaping unit 22 in the first direction X, thereby forming a powder layer24 ₂ having the thickness J (see (D) in FIG. 2). This powder layer 24 ₂formed in the current set of processes is layered over the powder layer24 ₁ including the dots 30, which were formed in the previous set ofprocesses.

The information processing device 14 controls the shaping device 12 torepeat the set of processes illustrated in FIG. 2. The informationprocessing device 14 determines the intervals of the set of processessuch that a new set of processes, in which a new powder layer 24 isformed and the shaping liquid 28 is ejected to the new powder layer 24,starts before the surface of the dots 30 that were formed at the powderlayer 24 in the previous set of processes, dries (the set of processesillustrated in (C), (D), (A), and (B) in FIG. 2).

The information processing device 14 controls the shaping device 12 torepeat the set of processes described above, whereby powder layers 24including dots 30 are layered in the shaping unit 22 and regions of thedots 30 in the powder layers 24 are joined to form a three-dimensionalshaped object 31.

The procedure for shaping a three-dimensional shaped object will bedescribed more specifically. FIG. 3 is a schematic view illustrating anexample of the procedure for shaping a three-dimensional shaped object.

When the shaping liquid 28 is ejected to a powder layer 24 ₁ formed bythe leveling unit 16, a dot 30 ₁ (dot 30) is formed at the powder layer24 ₁ (see (A) in FIG. 3). A powder layer 24 ₂ is then formed on thepowder layer 24 ₁ at which the dot 30 ₁ is formed (see (B) in FIG. 3),and the shaping liquid 28 is ejected to the powder layer 24 ₂ to form adot 30 ₂ (see (C) in FIG. 3).

A powder layer 24 ₃ is formed on the powder layer 24 ₂ at which the dot30 ₂ is formed, and the shaping liquid 28 is ejected to the powder layer24 ₃ to form a dot 30 ₃ (see (D) in FIG. 3).

The dots 30 (dot 30 ₁ to 30 ₃) formed by the shaping liquid 28 ejectedto the powder layers 24 (powder layers 24 ₁ to 24 ₃) contain the powder20, in which at least a part of the coating layer of the powder 20 isdissolved and is combined with each other. A new powder layer 24 isformed on the previous powder layer 24 and a new dot 30 is formed at thenew powder layer 24 before the surface of the dot 30 formed at theprevious powder layer 24 becomes dry. With this configuration, dotregions formed by the dots 30 in the powder layers 24 are successivelysolidified. The successively solidified regions (regions of the dots 30₁ to 30 ₃ in FIG. 3) become the three-dimensional shaped object 31.

At (A) to (D) in FIG. 3, for example, dots 30 are formed one by one inthe thickness direction of the powder layers 24. However, a plurality ofdots 30 may be formed in the horizontal direction (on a plane defined bythe first direction X and the Y direction) of the powder layer 24depending on the shaping target (see (E) in FIG. 3).

The information processing device 14, in some cases, receives a stopsignal that indicates a stop of operation while the set of processes ofsupplying the powder 20, forming the powder layer 24, and ejecting theshaping liquid 28 is repeated.

Operation is stopped for various reasons. Operation is stopped when, forexample, the maintenance unit 29 performs maintenance on the ejectionunit 26 or the user instructs emergency shutdown via the UI unit 36.

The information processing device 14 stops the set of processes onreceiving a stop signal. When the cause of the stop of operationindicated by the stop signal is eliminated, the information processingdevice 14 resumes the set of processes.

In this situation, in some cases, a dot 30 formed by the shaping liquid28 ejected to a powder layer 24 before the stop of the set of processesdoes not combine with a dot 30 formed by the shaping liquid 28 ejectedto a newly formed powder layer 24 after the resuming of the set ofprocesses, which may create discontinuity between the dots 30.

FIG. 4 is a schematic view illustrating an example of a phenomenon wherediscontinuity is created between dots 30 in powder layers 24.

When, for example, the shaping liquid 28 is ejected to a powder layer 24₁ formed by the leveling unit 16, a dot 30 ₁ (dot 30) is formed at thepowder layer 24 ₁ (see (A) in FIG. 4). A powder layer 24 ₂ is thenformed on the powder layer 24 ₁ (see (B) in FIG. 4), and the shapingliquid 28 is ejected to the powder layer 24 ₂ to form a dot 30 ₂ (see(C) in FIG. 4).

Suppose that the information processing device 14 controls the shapingdevice 12 to stop the set of processes at this point. Then, the surfaceof the dot 30 ₂ formed at the powder layer 24 ₂ before the stop of theoperation permeates into the powder layer 24 ₂ or becomes dry in somecases to the extent that discontinuity is created between the dot 30 ₂and a dot 30 ₃ at a powder layer 24 ₃ to be formed after the resuming ofthe operation (see (D) in FIG. 4).

In this state, suppose that the information processing device 14controls the shaping device 12 to resume the set of processes and toform the powder layer 24 ₃ on the powder layer 24 ₂ and the dot 30 ₃ atthe powder layer 24 ₃. The dot 30 ₂ formed at the powder layer 24 ₂before the stop of the operation does not combine with the dot 30 ₃formed at the powder layer 24 ₃ after the resuming of the operation insome cases and a gap P is formed between dots 30 (between the dot 30 ₂and the dot 30 ₃), which may result in discontinuity between dots 30(see (E) in FIG. 4).

In some cases, as described above, a dot 30 formed by the shaping liquid28 ejected onto a powder layer 24 before the stop of the set ofprocesses does not combine with a dot 30 formed by the shaping liquid 28ejected onto a newly formed powder layer 24 after the resuming of theset of processes, which may create discontinuity between the dots 30.Thus, in the typical technique known to the inventor, strength lossoccurs in the resulting three-dimensional shaped object 31 when theoperation is stopped in the middle of the set of processes for shapingthe three-dimensional shaped object 31.

In the three-dimensional shaping apparatus 10 according to the presentembodiment, the information processing device 14 performs a particularcontrol.

FIG. 5 is a functional block diagram of the three-dimensional shapingapparatus 10 according to the present embodiment. The three-dimensionalshaping apparatus 10 includes the UI unit 36, a storage unit 38, theinformation processing device 14, and the shaping device 12. The UI unit36, the storage unit 38, and the shaping device 12 are connected withthe information processing device 14 to be able to send and receive dataand signals to and from each other. The storage unit 38 stores thereinvarious kinds of data.

The information processing device 14 is a computer configured by, forexample, a central processing unit (CPU), and controls the entirethree-dimensional shaping apparatus 10. The information processingdevice 14 may be configured by other devices than a general-purpose CPU.The information processing device 14 may be configured by, for example,a circuit.

The information processing device 14 includes a reception unit 14A andthe control unit 14B. A part or all of the reception unit 14A and thecontrol unit 14B may be implemented by, for example, causing aprocessing device such as the CPU to execute a computer program, thatis, implemented by software or may be implemented by hardware such as anintegrated circuit (IC), or may be implemented by both software andhardware.

The reception unit 14A receives a stop signal indicating a stop ofoperation and a resume signal indicating resuming of the operation.

For example, the information processing device 14 controls the ejectionunit 26 and the maintenance unit 29 such that the maintenance unit 29performs maintenance on the ejection unit 26 at certain intervals. Thecertain intervals may be determined as appropriate depending on themechanism of the ejection unit 26, the type of the shaping liquid 28,and the installation environment of the three-dimensional shapingapparatus 10. The certain intervals may be changeable by an instructionfrom the user through the UI unit 36.

When the maintenance unit 29 starts performing maintenance on theejection unit 26 under the control of the information processing device14, the maintenance unit 29 may transmit a stop signal indicating a stopof operation to the information processing device 14. In this case, thereception unit 14A receives the stop signal from the maintenance unit29.

The maintenance unit 29 transmits a resume signal indicating resuming ofthe operation to the information processing device 14 when themaintenance of the ejection unit 26 is completed. In this case, thereception unit 14A receives the resume signal from the maintenance unit29.

The reception unit 14A may receive the stop signal from the UI unit 36.The user operates, for example, predetermined buttons on the UI unit 36for instructing a stop of the set of processes. Upon receiving theoperation from the user, the UI unit 36 transits a stop signal to theinformation processing device 14. In this case, the reception unit 14Aof the information processing device 14 receives the stop signal formthe UI unit 36.

The reception unit 14A receives a resume signal indicating resuming ofthe operation from the UI unit 36. The user operates, for example,predetermined buttons on the UI unit 36 for instructing resuming of theoperation. Upon receiving the operation from the user, the UI unit 36transmits a resume signal to the information processing device 14. Inthis case, the reception unit 14A of the information processing device14 receives the resume signal form the UI unit 36.

In the context of the present embodiment, the reception unit 14Areceives the stop signal and the resume signal from the maintenance unit29 or the UI unit 36.

The control unit 14B controls the supply unit 18, the leveling unit 16,and the ejection unit 26 to repeat the set of processes of supplying thepowder 20, forming the powder layer 24, and ejecting the shaping liquid28. Under the control of the control unit 14B, the three-dimensionalshaped object 31 corresponding to a shaping target is shaped.

Specifically, the control unit 14B generates print data with which theshaping device 12 can shape the three-dimensional shaped object 31, fromimage data representing the shaping target. The print data may begenerated by a known method. The control unit 14B may acquire the imagedata from an external device via a communication line, or from thestorage unit 38. The control unit 14B may generate the print data basedon the acquired image data.

The control unit 14B controls the shaping device 12 to repeat the set ofprocesses in accordance with the print data to shape thethree-dimensional shaped object 31 corresponding to the shaping target.

In the present embodiment, the control unit 14B stops the set ofprocesses when the reception unit 14A receives a stop signal. When thereception unit 14A receives a resume signal after receiving the stopsignal, the control unit 14B controls the supply unit 18, the levelingunit 16, and the ejection unit 26 to eject the shaping liquid 28 onto atleast a part of a dot region on the surface of the outermost powderlayer 24, the dot region being formed by dots 30 formed at the outermostpowder layer 24, and then resume the set of processes.

FIG. 6 is a schematic view illustrating an example of the procedure forshaping a three-dimensional shaped object performed in thethree-dimensional shaping apparatus 10 according to the presentembodiment after the set of processes is stopped and then resumed.

Suppose that the supply unit 18 and the leveling unit 16 supply thepowder 20 to the shaping unit 22, and the leveling unit 16 levels thesurface of the powder 20 in the first direction X to form, for example,a first powder layer 24 (powder layer 24 ₁) (see (A) in FIG. 6).

The ejection unit 26 then ejects the shaping liquid 28 to a position onthe surface of the powder layer 24 ₁ corresponding to a shaping target(see (A) in FIG. 6). Dots 30 ₁ formed by the shaping liquid 28 areformed at the powder layer 24 ₁ (see (B) in FIG. 6).

Suppose that the reception unit 14A receives a stop signal.

The control unit 14B stops the set of processes. The shaping process inthe shaping unit 22 is temporarily stopped with the powder layer 24 ₁formed with the dots 30 ₁ (see (B) in FIG. 6).

The reception unit 14A receives a resume signal. The control unit 14Bthen controls the ejection unit 26 to eject the shaping liquid 28 ontoat least a part of a dot region on the surface of the outermost powderlayer 24 ₁, the dot region being formed by the dots 30 ₁ formed at thepowder layer 24 ₁ (see (C) in FIG. 6).

In other words, upon reception of the resume signal after the stop ofthe set of processes, the control unit 14B causes the ejection unit 26to eject the shaping liquid 28 onto at least a part of the dot region onthe surface of the existing outermost powder layer 24 ₁, the dot regionbeing formed by the dots 30 ₁ formed at the powder layer 24 ₁, beforethe next powder layer 24 ₂ is formed. By this process, dots 32 formed bythe newly ejected shaping liquid 28 are formed on the dots 30 ₁ (see (D)in FIG. 6).

The dots 32, which are not included in the print data of the shapingtarget, are formed in contact with the dots 30 ₁, which are formed inaccordance with the print data of the shaping target, at the surface ofthe outermost powder layer 24 ₁ that was formed before the stop of theset of processes (see (D) in FIG. 6).

Subsequently, the control unit 14B controls the supply unit 18, theleveling unit 16, and the ejection unit 26 to resume the set ofprocesses after the dots 32 are formed by the ejection of the shapingliquid 28.

In other words, the support 22B moves the stage 22C vertically downwards(in the direction of the arrow ZB) by a predetermined amount (an amountcorresponding to the thickness J, for example) under the control of thecontrol unit 14B (see (E) in FIG. 6). This process creates a space atthe opening of the shaping chamber 22A for receiving newly suppliedpowder 20 from the supply unit 18. The support 18B moves the stage 18Cvertically upwards (in the direction of the arrow ZA) by a predeterminedamount (an amount corresponding to the thickness J, for example) underthe control of the control unit 14B. This process pushes up a part ofthe powder 20 stored in the supply chamber 18A above the opening of thesupply chamber 18A (see (E) in FIG. 6).

The leveling unit 16 initially disposed upstream of the supply unit 18in the first direction X moves downstream along the first direction Xunder the control of the control unit 14B. The powder 20 above theopening of the supply chamber 18A is supplied to the shaping unit 22(see (E) and (F) in FIG. 6).

The leveling unit 16 moves further downstream in the first direction X.In this operation, the leveling unit 16 levels the surface of the powder20 supplied to the shaping unit 22 in the first direction X, therebyforming a powder layer 24 ₂ having the thickness J (see (F) in FIG. 6).Then, the shaping liquid 28 is ejected onto the powder layer 24 ₂ in thesame manner as illustrated at (A) in FIG. 6, and the set of processes isrepeated.

FIG. 7 is a view illustrating the state of the dots 30 and the dot 32 inthe three-dimensional shaping apparatus 10 according to the presentembodiment when the set of processes is resumed after the stop thereof.

When the shaping liquid 28 is ejected to a powder layer 24 ₁, a dot 30 ₁(dot 30) is formed at the powder layer 24 ₁ (see (A) in FIG. 7). Apowder layer 24 ₂ is then formed on the powder layer 24 ₁ (see (B) inFIG. 7) and the shaping liquid 28 is ejected to the powder layer 24 ₂ toform a dot 30 ₂ (see (C) in FIG. 7).

Suppose that the control unit 14B performs control to stop the set ofprocesses at this point. Then, in some cases, the dot 30 ₂ formed at thepowder layer 24 ₂ permeates into the powder layer 24 ₂ or becomes dryduring the stop to the extent that discontinuity is created between thedot 30 ₂ and a dot 30 ₃ formed by the shaping liquid 28 to be ejectedonto a newly formed powder layer 24 ₃ (see (D) in FIG. 7).

In the present embodiment, as described above, the control unit 14Bcauses the shaping liquid 28 to be ejected onto the dot 30 ₂ on thepowder layer 24 ₂ at the resuming of the operation to form a dot 32 (see(E) in FIG. 7).

Any amount of the shaping liquid 28 may be ejected to form the dot 32 aslong as a droplet (dot 32) of the shaping liquid 28 having a thickness Tlarger than zero and equal to or smaller than the thickness J of thepowder layer 24 is made to present on the surface of the powder layer 24₂ (the outermost powder layer 24 before the stop of the operation) atthe time of the resuming of the operation.

It is preferable that the amount of the shaping liquid 28 to be ejectedto form the dot 32 is determined such that the a droplet (dot 32) of theshaping liquid 28 having the thickness T exists on the surface of thepowder layer 24 ₂ (the outermost powder layer 24 at the time of the stopof the operation) when a new powder layer 24 ₃ is formed and the shapingliquid 28 is ejected thereto in the set of processes immediately afterthe resuming of the operation.

The control unit 14B performs control to resume the set of processes.Then, the new powder layer 24 ₃ and a dot 30 ₃ are formed on the dot 32(see (F) in FIG. 7).

With this configuration, the dot 30 (dot 30 ₂ at (F) in FIG. 7) formedby the shaping liquid 28 ejected onto the powder layer 24 before thestop of the set of processes combines with a dot 30 (dot 30 ₃ at (F) inFIG. 7) formed by the shaping liquid 28 ejected onto a powder layer 24that is newly formed after the resuming of the set of processes via thedot 32 formed by the shaping liquid 28 ejected after the stop and beforethe resuming of the set of processes, thereby forming contiguous dots.

Thus, the shaping device 12 according to the present embodiment canprevent strength loss in the resulting three-dimensional shaped object31 even if the set of processes is stopped in the middle of the shaping.

Upon reception of a resume signal after the reception of a stop signal,the shaping liquid 28 may be ejected to at least a part of the dotregion on the surface of the existing outermost powder layer 24, the dotregion being formed by the dots 30 formed at the powder layer 24.

FIG. 8 is a view illustrating regions to which the shaping liquid 28 isejected upon reception of a resume signal after the reception of a stopsignal.

Suppose that, for example, an existing outermost powder layer 24 _(n) isalready formed with a dot region Q formed by the dots 30 _(n) when thecontrol unit 14B receives a stop signal (see (A) in FIG. 8).

In this case, for example, upon reception of the resume signal after thestop of the set of processes, the control unit 14B may cause the shapingliquid 28 to be ejected onto regions QA that are a part of the dotregion Q on the surface of the outermost powder layer 24 _(n) the dotregion Q being formed by the dots 30 _(n) formed at the powder layer 24_(n) (see (B) in FIG. 8).

It is preferable that upon reception of the resume signal after the stopof the set of processes, the control unit 14B causes the shaping liquid28 to be ejected onto a region QB inside the outline of the dot region Qon the surface of the outermost powder layer 24 _(n), the dot region Qbeing formed by the dots 30 _(n) formed at the powder layer 24 _(n) (see(C) in FIG. 8).

Suppose that, for example, the dot region Q on the surface of theoutermost powder layer 24 _(n) is formed by a plurality of dots 30 _(n)disposed in the horizontal plane (XY plane), the dot region Q beingformed by the plurality of dots 30 _(n) formed at the powder layer 24_(n). In this case, it is preferable that the control unit 14B causesthe shaping liquid 28 to be ejected onto dots 30 _(n) inside the dots 30_(n) aligned along the outline of the dot region Q.

Upon reception of the resume signal after the stop of the set ofprocesses, the control unit 14B may cause the shaping liquid 28 to beejected onto the dot region Q (that is, onto a region identical to thedot region Q) on the surface of the outermost powder layer 24 _(n), thedot region Q being formed by the dots 30 _(n) formed at the powder layer24 _(n).

Upon reception of the resume signal after the stop of the set ofprocesses, the control unit 14B may cause any amount of the shapingliquid 28 to be ejected onto the surface of the outermost powder layer24 _(n) as long as a droplet (dot 32) of the shaping liquid 28 havingthe thickness T larger than zero and equal to or smaller than thethickness J is made to present on the surface of the powder layer 24_(n) at the time of the resuming of the operation, as described above.

Further, it is preferable that the control unit 14B adjusts the ejectionamount of the shaping liquid 28 in accordance with the standby timebetween the reception of the stop signal and the reception of the resumesignal such that the thickness T is achieved.

For example, the control unit 14B stores, in the storage unit 38, inadvance the relation between the standby time and the amount of theshaping liquid 28 to be ejected to the outermost powder layer 24 _(n)after the reception of the stop signal. This amount of the shapingliquid 28 corresponds to an amount ejected from a nozzle at one shot tothe outermost powder layer 24 _(n) after the reception of the stopsignal.

The shaping device 12 measures in advance the standby time between thereception of a stop signal and the reception of a resume signal, and theamount of the shaping liquid 28 that can form the droplet having thethickness T in the three-dimensional shaping apparatus 10. The controlunit 14B of the shaping device 12 may store the standby time and theejection amount of the shaping liquid 28 in the storage unit 38 inassociation with each other in advance.

FIGS. 9A and 9B are a graph and a view illustrating an example of therelation between the standby time and the amount of the shaping liquidto be ejected. FIG. 9A illustrates a graph 60 illustrating an example ofthe relation between the standby time and the amount of the shapingliquid to be ejected. In FIG. 9A, t₁, t₂, and t₃ each represent astandby time t. The relation between t₁, t₂, and t₃ is represented by aninequality 0<t₁<t₂<t₃.

For example, the amount of the shaping liquid 28 necessary for achievingthe thickness T increases with the standby time until the standby timereaches a certain time. However, when the standby time exceeds thecertain time, the thickness T can be achieved with a smaller amount ofthe shaping liquid 28.

Specifically, as illustrated in FIG. 9A, when the standby time t is zeroor more and less than t₁, the control unit 14B determines that thedroplet (dot 32) of the shaping liquid 28 is still present on thesurface of the powder layer 24. When the standby time is within thisperiod (0≦t<t₁), the control unit 14B controls the supply unit 18 andthe leveling unit 16 to supply the powder 20 onto the powder layer 24without ejection of the shaping liquid 28.

When the standby time t is t₁ or more and less than t₂, the control unit14B determines that the droplet (dot 32) of the shaping liquid 28 is notpresent on the surface of the powder layer 24. Specifically, the controlunit 14B determines that the droplet (dot 32) of the shaping liquid 28having the thickness T is not present on the surface of the powder layer24 that is the outermost layer at the time of the stop of the operation.

The surface (powder surface) of the powder layer 24 becomes dry. Thus,the control unit 14B controls the ejection unit 26 to eject the shapingliquid 28 before the next powder layer 24 is formed. As the standby timet increases, the dry region (region in the thickness direction of thepowder layer 24) increases. In this case, a larger amount of shapingliquid 28 needs to be ejected to form the droplet (dot 32) of theshaping liquid 28 having the thickness T on the dry region of the powderlayer 24. Accordingly, the control unit 14B controls the ejection unit26 to eject a larger amount of the shaping liquid 28 as the standby timet increases from t₁ to t₂.

However, once the standby time t exceeds t₂, the powder 20 startsreacting with the shaping liquid 28 and starts solidifying. FIG. 9B is adiagram illustrating a state in which the powder 20 starts reacting withthe shaping liquid 28 and starts solidifying. As illustrated in FIG. 9B,the shaping liquid 28 forms a liquid bridge between particles of thepowder 20 (between a powder particle 20A and a powder particle 20B).When solidification is achieved while a liquid bridge is formed, thesurface of the powder 20 forms something like a wall. In other words, awall of liquid bridges is formed near the surface of the powder layer24.

Such a wall of liquid bridges formed near the surface of the powderlayer 24 prevents the shaping liquid 28 from further permeating into thepowder layer 24 even when a large amount of shaping liquid 28 is ejectedonto the powder layer 24. In other words, when the standby time texceeds t₂, the region of the wall of liquid bridges increases. Thus, asmaller amount of the shaping liquid 28 is ejected onto the surface ofthe powder layers 24 to form a droplet (dot 32) of the shaping liquid 28having the thickness T as the standby time t proceeds from t₂ to t₃.Accordingly, the control unit 14B controls the ejection unit 26 to ejecta smaller amount of shaping liquid 28 when the standby time t is t₂ ormore and less than t₃.

When the standby time t is t₃ or more, the reaction between the powder20 and the shaping liquid 28 is completed. Consequently, as indicated inFIG. 9A, a necessary amount of shaping liquid 28 to cause a droplet (dot32) of the shaping liquid 28 having the thickness T to present on thesurface of the powder layer 24 becomes approximately constant. Thecontrol unit 14B controls the ejection unit 26 to cause an ejectionamount of the shaping liquid 28 to be approximately constant when thestandby time t is t₃ or more.

The standby time t₁, t₂, and t₃ may be measured in advance. The controlunit 14B of the shaping device 12 may store the standby time and theamount of the shaping liquid 28 to be ejected that is represented by thegraph 60 in FIG. 9A, in the storage unit 38 in association with eachother in advance. The control unit 14B may read the amount of theshaping liquid 28 to be ejected corresponding to the standby time fromthe storage unit 38, and use the read amount as an amount of the shapingliquid 28 to be ejected onto the outermost powder layer 24 uponreception of a resume signal after the stop of the set of processes.

It is preferable that upon reception of the resume signal after the stopof the set of processes, the control unit 14B controls the ejection unit26 to eject the shaping liquid 28 a plurality of times to the surface ofthe outermost powder layer 24.

FIGS. 10A and 10B are schematic views illustrating an example of thestate of the powder layer 24 when the shaping liquid 28 is ejectedthereto. When the ejection unit 26 ejects the shaping liquid 28 to thesurface of the powder layer 24 and the shaping liquid 28 lands thereon,some particles of the powder 20 on the powder layer 24 are blown up insome cases. As more amount of the shaping liquid 28 is ejected from theejection unit 26 at one shot, more particles of the powder 20 are blownup.

Thar is, ejecting a large droplet of the shaping liquid 28 to the powderlayer 24 blows up more particles of the powder 20 (see FIG. 10A) thanthe particles of the powder 20 blown up when a small droplet of theshaping liquid 28 is ejected to the powder layer 24 (see FIG. 10B).

Thus, it is preferable that the control unit 14B controls the ejectionunit 26 to eject the shaping liquid 28 a plurality of times to thesurface of the outermost powder layer 24 upon reception of the resumesignal after the stop of the set of processes.

Described next is the procedure of the shaping processing executed bythe information processing device 14 according to the presentembodiment. FIG. 11 is a flowchart illustrating an example of theprocedure of the shaping processing.

First, the control unit 14B generates print data with which the shapingdevice 12 can shape a three-dimensional shaped object, from image datarepresenting a shaping target (Step S102). The control unit 14B thencontrols the shaping device 12 to shape the three-dimensional shapedobject 31 corresponding to the shaping target using the print data.

Specifically, the control unit 14B controls the supply unit 18 to supplythe powder 20 (Step S104). In the present embodiment, the control unit14B controls the actuation of the leveling unit 16, the actuation of thesupport 18B of the supply unit 18, and the actuation of the support 22Bto supply the powder 20. By the processing at Step S104, the powder 20is supplied to the shaping unit 22.

The control unit 14B controls the leveling unit 16 to form a powderlayer 24 (Step S106). In the present embodiment, the control unit 14Bcontrols the leveling unit 16 to level the surface of the powder 20supplied to the shaping unit 22 in the first direction X to form apowder layer 24 having the thickness J. By the processing at Step S106,the powder layer 24 is formed.

The control unit 14B controls the ejection unit 26 to eject the shapingliquid 28 (Step S108). In the present embodiment, the control unit 14Bcontrols the ejection unit 26 to eject the shaping liquid 28 topositions on the surface of the powder layer 24 corresponding to theshaping target in accordance with the print data generated at Step S102to form dots 30. By the processing at Step S108, the shaping liquid 28is ejected to the powder layer 24 and the dots 30 are formed.

The control unit 14B determines whether to end the set of processes fromStep S104 to Step S108 (Step S110). The control unit 14B determines, atStep S110, whether the set of processes has been repeated a certainnumber of times necessary for shaping the three-dimensional shapedobject in accordance with the print data generated at Step S102.

If no at Step S110 (No at Step S110), the control unit 14B executes theprocessing at Step S104 again. If yes at Step S110 (Yes at Step S110),the control unit 14B ends this routine.

The information processing device 14 according to the present embodimentexecutes interruption processing illustrated in FIG. 12 in the middle ofthe procedure illustrated in FIG. 11. FIG. 12 is a flowchartillustrating an example of the procedure of the interruption processing.

First, the reception unit 14A determines whether a stop signalindicating a stop of operation has been received (Step S200). If no atStep S200 (No at Step S200), the control unit 14B ends this routine.

If yes at Step S200 (Yes at Step S200), the control unit 14B executesthe processing at Step S202. At Step S202, the control unit 14B controlsthe shaping device 12 to complete processes up to the control of theejection of the shaping liquid 28 by the ejection unit 26 in the currentroutine of the set of processes (Step S202).

The control unit 14B starts a timer to measure the standby time (StepS204). The standby time is, as described above, a time period from thereception of a stop signal to the reception of a resume signal. In thisroutine, for example, the standby time is a time period starting fromthe completion of the current set of processes after the reception ofthe stop signal and ending upon reception of the resume signal.

The control unit 14B controls the shaping device 12 to stop the set ofprocesses (Step S206).

The control unit 14B determines whether the stop signal received at StepS200 is transmitted for the purpose of maintenance (Step S208). Thisdetermination at Step S208 is made such that the control unit 14Bdetermines whether the stop signal is transmitted from the maintenanceunit 29.

If yes at Step S208 (Yes at Step S208), the control unit 14B executesthe processing at Step S210. The control unit 14B controls themaintenance unit 29 to start maintenance work on the ejection unit 26(Step S210). By the processing at Step S210, the maintenance of theejection unit 26 by the maintenance unit 29 is started. The control unit14B then executes the processing at Step S212.

If no at Step S208 (No at Step S208), the control unit 14B executes theprocessing at Step S212.

At Step S212, the control unit 14B repeats negative determination (No atStep S212) until the reception unit 14A determines that a resume signalhas been received (Yes at Step S212). If yes at Step S212 (Yes at StepS212), the control unit 14B executes the processing at Step S214.

At Step S214, the control unit 14B stops the timer started at Step S204(Step S214). Then, the control unit 14B calculates the time period fromthe starting of the timer at Step S204 to the ending of the timer atStep S214 to calculate the standby time (Step S216).

The control unit 14B reads the amount of the shaping liquid 28 to beejected corresponding to the standby time calculated at Step S216, fromthe storage unit 38 (Step S218). Then, the control unit 14B cause theshaping liquid 28, whose amount is read at Step S218, to be ejected ontoat least a part of a dot region on the surface of the existing outermostpowder layer 24, the dot region being formed by the dots 30 formed atexisting outermost the powder layer 24 (Step S220).

The control unit 14B controls the shaping device 12 to resume the set ofprocesses (Step S222). The processing at Step S222 is the processingexecuted at Steps S104 to S110 in FIG. 11. The control unit 14B thenends this routine.

As described above, the three-dimensional shaping apparatus 10 accordingto the present embodiment includes the supply unit 18, the leveling unit16, the ejection unit 26, the control unit 14B, and the reception unit14A. The supply unit 18 supplies the powder 20. The leveling unit 16levels the surface of the supplied powder 20 in the first direction X toform a powder layer 24. The ejection unit 26 ejects the shaping liquid28 to a position on the surface of the powder layer 24 corresponding toa shaping target to form a dot 30.

The control unit 14B controls the supply unit 18, the leveling unit 16,and the ejection unit 26 to repeat the set of processes of supplying thepowder 20, forming the powder layer 24, and ejecting the shaping liquid28 to shape a three-dimensional shaped object 31 corresponding to theshaping target. The reception unit 14A receives a stop signal indicatinga stop of operation and a resume signal indicating resuming of theoperation.

The control unit 14B stops the set of processes upon reception of thestop signal, and upon reception of the resume signal after the receptionof the stop signal, the control unit 14B controls the supply unit 18,the leveling unit 16, and the ejection unit 26 to eject the shapingliquid 28 onto at least a part of a dot region Q on the surface of theoutermost powder layer 24, the dot region being formed by the dot 30formed at the powder layer 24, and then resume the set of processes.

In the three-dimensional shaping apparatus 10 according to the presentembodiment, the shaping liquid 28 is ejected onto at least a part of thedot region Q formed by the dot 30 on the existing outermost powder layer24 before resuming of the set of processes that is resumed uponreception of the resume signal.

With this configuration, the dot 30 formed at the powder layer 24 beforethe stop of the set of processes combines with a dot 30 formed by theshaping liquid 28 on a new powder layer 24 that is formed after resumingof the set of processes via the dot 32 formed by the shaping liquid 28ejected after the stop and before the resuming of the set of processes,thereby forming contiguous dots (see FIG. 7).

Thus, the shaping device 12 according to the present embodiment canprevent strength loss in the resulting three-dimensional shaped object31 even if the set of processes is stopped and then resumed in themiddle of the shaping of the three-dimensional shaped object 31.

The shaping device 12 according to the present embodiment can preventstrength loss in the three-dimensional shaped object 31.

It is preferable that upon reception of the resume signal after thereception of the stop signal, the control unit 14B controls the supplyunit 18, the leveling unit 16, and the ejection unit 26 to eject theshaping liquid 28 a plurality of times onto at least a part of the dotregion Q on the surface of the outermost powder layer 24, the dot regionbeing formed by the dot 30 formed at the powder layer 24, and thenresume the set of processes.

It is preferable that upon reception of the resume signal after thereception of the stop signal, the control unit 14B controls the supplyunit 18, the leveling unit 16, and the ejection unit 26 to eject anamount of the shaping liquid 28 onto at least a part of the dot region Qformed by the dot 30 formed at the powder layer 24, the amount of theshaping liquid 28 being such that a droplet of the shaping liquid 28having a thickness larger than zero and equal to or smaller than thethickness J is made to present on the surface of the powder layer 24 atthe time of the resuming of the operation, and then resume the set ofprocesses.

It is preferable that upon reception of the resume signal after thereception of the stop signal, the control unit 14B controls the supplyunit 18, the leveling unit 16, and the ejection unit 26 to eject anamount of the shaping liquid 28 onto at least a part of the dot region Qon the surface of the outermost powder layer 24, the dot region beingformed by the dot 30 formed at the powder layer 24, the amount of theshaping liquid 28 depending on a standby time from the reception of thestop signal to the reception of the resume signal, and then resume theset of processes.

It is preferable that upon reception of the resume signal after thereception of the stop signal, the control unit 14B controls the supplyunit 18, the leveling unit 16, and the ejection unit 26 to eject theshaping liquid 28 onto a region inside the outline of the dot region Qon the surface of the outermost powder layer 24, the dot region Q beingformed by the dot 30 formed at the powder layer 24, and then resume theset of processes.

The three-dimensional shaping method according to the present embodimentis a method performed by the three-dimensional shaping apparatus 10including the supply unit 18 that supplies the powder 20, the levelingunit 16 that levels the surface of the supplied powder 20 in the firstdirection X to form a powder layer 24, and the ejection unit 26 thatejects the shaping liquid 28 to a position corresponding to a shapingtarget on the surface of the powder layer 24 to form a dot 30. Thethree-dimensional shaping method according to the present embodimentincludes controlling the supply unit 18, the leveling unit 16, and theejection unit 26 to repeat a set of processes of supplying the powder20, forming the powder layer 24, and ejecting the shaping liquid 28 toshape the three-dimensional shaped object 31 corresponding to theshaping target, and receiving a stop signal indicating a stop ofoperation and a resume signal indicating resuming of the operation. Thecontrolling includes stopping the set of processes upon reception of thestop signal, and upon reception of the resume signal after the receptionof the stop signal, controlling the supply unit 18, the leveling unit16, and the ejection unit 26 to eject the shaping liquid 28 onto atleast a part of a dot region Q on the surface of the outermost powderlayer 24, the dot region Q being formed by the dot 30 formed at thepowder layer 24, and then resume the set of processes.

The three-dimensional shaping computer program according to the presentembodiment is a computer program that is executed by a computer thatcontrols the shaping device 12 including the supply unit 18 thatsupplies the powder 20, the leveling unit 16 that levels the surface ofthe supplied powder 20 in the first direction X to form a powder layer24, and the ejection unit 26 that ejects the shaping liquid 28 to aposition corresponding to a shaping target on the surface of the powderlayer 24 to form a dot 30. The three-dimensional shaping computerprogram according to the present embodiment includes controlling thesupply unit 18, the leveling unit 16, and the ejection unit 26 to repeata set of processes of supplying the powder 20, forming the powder layer24, and ejecting the shaping liquid 28 to shape the three-dimensionalshaped object 31 corresponding to the shaping target, and receiving astop signal indicating a stop of operation and a resume signalindicating resuming of the operation. The controlling includes stoppingthe set of processes upon reception of the stop signal, and uponreception of the resume signal after the reception of the stop signal,controlling the supply unit 18, the leveling unit 16, and the ejectionunit 26 to eject the shaping liquid 28 onto at least a part of a dotregion Q on the surface of the outermost powder layer 24, the dot regionbeing formed by the dot 30 formed at the powder layer 24, and thenresume the set of processes.

The information processing device 14 according to the present embodimentcontrols the shaping device 12 including the supply unit 18 thatsupplies the powder 20, the leveling unit 16 that levels the surface ofthe supplied powder 20 in the first direction X to form a powder layer24, and the ejection unit 26 that ejects the shaping liquid 28 to aposition corresponding to a shaping target on the surface of the powderlayer 24 to form a dot 30. The information processing device 14 includesthe reception unit 14A and the control unit 14B.

The control unit 14B controls the supply unit 18, the leveling unit 16,and the ejection unit 26 to repeat a set of processes of supplying thepowder 20, forming the powder layer 24, and ejecting the shaping liquid28 to shape a three-dimensional shaped object 31 corresponding to theshaping target. The reception unit 14A receives a stop signal indicatinga stop of operation and a resume signal indicating resuming of theoperation.

Upon reception of the stop signal, the control unit 14B stops the set ofprocesses, and upon reception of the resume signal after the receptionof the stop signal, the control unit 14B controls the supply unit 18,the leveling unit 16, and the ejection unit 26 to eject the shapingliquid 28 onto at least a part of a dot region Q on the surface of theoutermost powder layer 24, the dot region being formed by the dot 30formed at the powder layer 24, and then resume the set of processes.

The following specifically describes the powder 20 and the shapingliquid 28 used in the present embodiment.

<Powder>

The powder 20 is made of a base material in a particulate form with thesurface covered with a coating layer. The powder 20 may contain othercomponents in addition to the base material.

Base Material

First, the base material is described. The base material is in apowdered or particulate form. The base material is made of, for example,metal, ceramic, carbon, polymer, wood, biocompatible material, or sand.To shape a stronger three-dimensional shaped object 31, it is preferableto use metal or ceramic that can be subjected to sintering processing.

Examples of the metal may include stainless steel (SUS), iron, copper,titanium, and silver. The stainless steel (SUS) is, for example,SUS316L. The ceramic is, for example, metal oxides. Specifically, theceramic is, for example, silica (SiO₂), alumina (Al₂O₃), zirconia(ZrO₂), or titania (TiO₂). The carbon is, for example, graphite,graphene, carbon nanotube, carbon nanohorn, or fullerene.

The polymer is, for example, a known water-insoluble resin. The wood is,for example, wood chip or cellulose. The biocompatible material is, forexample, polylactic acid or calcium phosphate.

The base material may contain one type of material of the aforementionedmaterials, or may contain a plurality of types of materials thereof.

The base material may be commercially available particles or powder madeof the aforementioned materials. Examples of the commercially availableparticles or powder may include SUS316L (PSS316L manufactured by SanyoSpecial Steel Co., Ltd.), SiO₂ (EXCELICA SE-15K manufactured by TokuyamaCorporation), AlO₂ (TAIMICRON TM-5D manufactured by Taimei ChemicalsCo., Ltd.), and ZrO₂ (TZ-B53 manufactured by Tosoh Corporation).

The base material may be subjected to known surface (modification)processing to enhance affinity to the coating layer (to be describedlater) that covers the surface of the base material.

The mean particle size of the base material may be selected asappropriate depending on the purpose, and thus is not limited to anyparticular value. For example, the mean particle size of the basematerial is preferably 0.1 μm or more and 500 μm or less, morepreferably 5 μm or more and 300 μm or less, and still more preferably 15μm or more and 250 μm or less.

When the base material has a mean particle size of 0.1 μm or more and500 μm or less, efficiency of fabrication of the three-dimensionalshaped object 31 is increased and the base material is easy to manage orhandle. When the base material has a mean particle size of 500 μm orless, the powder layer 24, which is formed by the powder 20, has ahigher density and thus the resulting three-dimensional shaped object 31can be less porous.

The mean particle size of the base material can be measured inaccordance with a known method using a known particle size analyzer suchas Microtrac HRA (manufactured by Nikkiso Co., Ltd.).

The particle size distribution of the base material may be selected asappropriate depending on the purpose, and thus is not limited to anyparticular value. The shape, surface area, circularity, fluidity,wettability, or other properties of the base material may be selected asappropriate depending on the purpose, and thus is not limited to anyparticular value.

Coating Layer

Described next is the coating layer that covers the surface of the basematerial. The coating layer has a function of dissolving in the shapingliquid 28 and then solidifying, and may be prepared depending on thetypes of the shaping liquid 28.

For example, the coating layer is preferably made of an organicmaterial.

The organic material is preferably dissolvable in the shaping liquid 28and cross-linkable by, for example, a cross-linking agent contained inthe shaping liquid 28.

The phrase that the organic material is dissolvable in the shapingliquid 28 means, for example, when 1 g of organic material is mixed with100 g of the shaping liquid 28 as a solvent at 30° C. and stirred, 90%by mass or more of the organic material dissolves in the solvent.

The viscosity of 4% by mass (w/w %) solution of the organic materialused for the coating layer at 20° C. is preferably 40 mPa·s or less,more preferably 1 mPa·s or more and 35 mPa·s or less, and particularlypreferably 5 mPa·s or more and 30 mPa·s or less.

When the aforementioned viscosity of the organic material used for thecoating layer is 40 mPa·s or less, the strength and dimensional accuracyof the resulting three-dimensional shaped object 31, which includes thedots 30 formed by the shaping liquid 28 ejected onto the powder 20,increase. The viscosity may be measured, for example, in accordance withJIS K7117.

The organic material used for the coating layer is a material that has afunction of dissolving in the shaping liquid 28 and then solidifying,and may be selected as appropriate depending on the purpose or the typesof the shaping liquid 28. The organic material used for the coatinglayer is preferably a water-soluble material in terms of manageabilityor environmental loads. Examples of the water-soluble organic materialmay include water-soluble resins and water-soluble prepolymers.

When the powder 20 contains a water-soluble organic material in thecoating layer, an aqueous medium can be used as the shaping liquid 28.When the coating layer is made of a water-soluble organic material, thepowder 20 can be separated into the organic material and the basematerial by water treatment in disposing of or recycling the powder 20.

Examples of the water-soluble resins may include polyvinyl alcoholresin, polyacrylic resin, cellulosic resin, starch, gelatin, vinylresin, amide resin, imide resin, acrylic resin, and polyethylene glycol.

These water-soluble resins may be homopolymers or heteropolymers(copolymers), or may be modified, as long as the water-soluble resinsexhibit water-soluble properties. The water-soluble resins mayincorporate a known functional group, or may be in the form of a salt.

When, for example, polyvinyl alcohol resin is used for the coatinglayer, the polyvinyl alcohol resin may be polyvinyl alcohol, modifiedpolyvinyl alcohol that is modified with an acetoacetyl group, an acetylgroup, or silicone (such as acetoacetyl-modified polyvinyl alcohol,acetyl-modified polyvinyl alcohol, or silicone-modified polyvinylalcohol), or butanediol vinyl alcohol copolymer.

When polyacrylic resin is used for the coating layer, the polyacrylicresin may be polyacrylic acid or salts thereof such as sodiumpolyacrylate. When cellulosic resin is used for the coating layer, thecellulosic resin may be cellulose or carboxymethyl cellulose (CMC). Whenacrylic resin is used for the coating layer, the acrylic resin may be,for example, polyacrylic acid or acrylic acid/maleic anhydridecopolymer.

When water-soluble prepolymer is used for the coating layer, thewater-soluble prepolymer may be, for example, an adhesive water-solubleisocyanate prepolymer contained in, for example, water stopping agents.

Examples of organic materials or resins that are water-insoluble andthat can be used for the coating layer may include acryl, maleic acid,silicone, butyral, polyester, polyvinyl acetate, vinyl chloride/vinylacetate copolymers, polyethylene, polypropylene, polyacetal,ethylene/vinyl acetate copolymers, ethylene/(meth)acrylic acidcopolymers, α-olefin/maleic anhydride based copolymers, esterifiedα-olefin/maleic anhydride based copolymers, polystyrene,poly(meth)acrylic ester, α-olefin/maleic anhydride/vinyl groupcontaining monomer copolymers, styrene/maleic anhydride copolymers,styrene/(meth)acrylic ester copolymers, polyamide, epoxy resin, xyleneresin, ketone resin, petroleum resin, rosin or derivatives thereof,coumarone-indene resin, terpene resin, polyurethane resin, syntheticrubbers such as styrene/butadiene rubber, polyvinyl butyral, nitrilerubber, acrylic rubber, and ethylene/propylene rubber, andnitrocellulose.

The coating layer is preferably made of an organic material having across-linkable functional group. The cross-linkable functional group maybe selected as appropriate depending on the purpose, and thus is notlimited to any particular type. Examples of the cross-linkablefunctional group may include a hydroxyl group, a carboxyl group, anamide group, a phosphate group, a thiol group, an acetoacetyl group, andan ether bond.

Using an organic material having a cross-linkable functional group forthe coating layer is preferable in that the organic material can easilycross-link with each other to form a solid three-dimensional shapedobject 31.

The organic material used for the coating layer is preferably apolyvinyl alcohol resin having a mean degree of polymerization of 400 ormore and 1100 or less. Furthermore, the organic material used for thecoating layer is preferably a modified polyvinyl alcohol resincontaining a cross-linkable functional group in molecules thereof. Inparticular, the coating layer is preferably made of anacetoacetyl-modified polyvinyl alcohol resin.

When, for example, the coating layer is made of a polyvinyl alcoholresin having an acetoacetyl group, the acetoacetyl group can easily forma complex three-dimensional network structure (cross-linking structure)via metal contained in a cross-linking agent in the shaping liquid 28(excellent in cross-linking reactivity). Thus, the resultingthree-dimensional shaped object 31 has considerably high flexuralstrength.

The coating layer may contain one types of polyvinyl alcohol resinhaving an acetoacetyl group (acetoacetyl-modified polyvinyl alcoholresins), or two or more types thereof that exhibit different propertiessuch as viscosity or saponification values. It is preferable to use anacetoacetyl-modified polyvinyl alcohol resin having a mean degree ofpolymerization of 400 or more and 1100 or less for the coating layer.

The coating layer may contain one types of the aforementioned organicmaterials or two or more types thereof, or may be made of an organicmaterial made by synthesis as appropriate or a commercially availableorganic material.

Examples of the commercially available organic material used for thecoating layer may include polyvinyl alcohol (PVA-205C, PVA-220Cmanufactured by Kuraray Co., Ltd.), polyacrylic acid (JURYMER AC-10manufactured by Toagosei Co., Ltd.), sodium polyacrylate (JURYMERAC-103P manufactured by Toagosei Co., Ltd.), acetoacetyl-modifiedpolyvinyl alcohol (GOHSENX Z-300, GOHSENX Z-100, GOHSENX Z-200, GOHSENXZ-205, GOHSENX Z-210, GOHSENX Z-220 manufactured by The Nippon SyntheticChemical Industry Co., Ltd.), carboxyl-modified polyvinyl alcohol(GOHSENX T-330, GOHSENX T-350, GOHSENX T-330T manufactured by The NipponSynthetic Chemical Industry Co., Ltd.), butanediol vinyl alcoholcopolymer (Nichigo G-Polymer OKS-8041 manufactured by The NipponSynthetic Chemical Industry Co., Ltd.), diacetone acrylamide-modifiedpolyvinyl alcohol (DF-05 manufactured by Japan Vam & Poval Co., Ltd.),sodium carboxymethyl cellulose (Cellogen 5A, Cellogen 6A manufactured byDKS Co. Ltd.), starch (HISTARD PSS-5 manufactured by Sanwa Starch Co.,Ltd.), and gelatin (beMatrix gelatin manufactured by Nitta GelatinInc.).

The thickness of the coating layer is not limited to any particularvalue, but, for example, the average thickness is preferably 5 nm ormore and 1000 nm or less, more preferably, 5 nm or more and 500 nm orless, still more preferably 50 nm or more and 300 nm or less, andparticularly preferably 100 nm or more and 200 nm or less.

When the average thickness of the coating layer is 5 nm or more, thestrength of the three-dimensional shaped object 31 that includes thedots 30 formed by the shaping liquid 28 ejected onto the powder 20increases. When the average thickness of the coating layer is 1000 nm orless, the dimensional accuracy of the three-dimensional shaped object 31that includes the dots 30 formed by the shaping liquid 28 ejected ontothe powder 20 increases.

The average thickness of the coating layer can be measured by, forexample, embedding the powder 20 in an acrylic resin, performing etchingor the like to expose a surface of the base material, and then using ascanning tunnel microscope (STM), an atomic force microscope (AFM), ascanning electron microscope (SEM), or the like.

When the coating layer is made of a material containing a cross-linkingagent, the coating layer can be made thinner than a coating layer thatdoes not contain a cross-linking agent. In other words, the hardeningeffect of the cross-linking agent can make the coating layer thinner,which can achieve both high strength and dimensional accuracy of theresulting three-dimensional shaped object 31.

The surface coverage (area ratio) of the base material with the coatinglayer may be adjusted as appropriate depending on the purpose, and thusis not limited to any particular value. For example, the surfacecoverage of the base material with the coating layer is preferably 15%or more, more preferably 50% or more, and particularly preferably 80% ormore.

When the surface coverage is 15% or more, the strength of thethree-dimensional shaped object 31 that includes the dots 30 formed bythe shaping liquid 28 ejected onto the powder 20 increases. When thesurface coverage is 15% or more, the dimensional accuracy of thethree-dimensional shaped object 31 that includes the dots 30 formed bythe shaping liquid 28 ejected onto the powder 20 increases.

The surface coverage of the base material with the coating layer ismeasured by, for example, observing a picture of the powder 20 taken byan electron microscope to obtain the ratio (%) of the area covered withthe coating layer to the entire surface area of the base material withrespect to each particle of the powder 20 in the picture, andcalculating the average. The average may be used as the surfacecoverage. Alternatively, the coverage may be measured by elementalmapping on the portion of the base material of the powder 20 coveredwith the coating layer using energy dispersive X-ray spectrometry suchas SEM/EDS.

The powder 20 may contain other components. Such other components may beselected as appropriate depending on the purpose, and thus are notlimited to any particular component. Examples of other components mayinclude a fluidizer, a filler, a leveling agent, and a sintering aid.

When the powder 20 contains a fluidizer, the powder 20 can form thepowder layer 24 easily and efficiently. When the powder 20 contains afiller, the resulting three-dimensional shaped object 31 can be lessporous. When the powder 20 contains a leveling agent, the wettability ofthe powder 20 increases and thus handleability of the powder 20increases. When the powder 20 contains a sintering aid, the resultingthree-dimensional shaped object 31, when sintered, can be sintered at alower temperature.

Method for Manufacturing Powder

The method for manufacturing the powder 20 may be selected asappropriate depending on the purpose, and thus is not limited to anyparticular method.

For example, the surface of the particles (powder) of the base materialmay be coated with a coating layer by a known coating method. Examplesof the known coating method may include a rolling fluidized coatingmethod, a spray drying method, a stirring mixing adding method, adipping method, and a kneader coating method. These coating methods canbe practiced by, for example, known commercially available coatingmachines or granulating machines.

Properties of Powder

The mean particle size of the powder 20 may be selected as appropriatedepending on the purpose, and thus is not limited to any particularvalue. For example, the mean particle size of the powder 20 ispreferably 3 μm or more and 250 μm or less, more preferably 3 μm or moreand 200 μm or less, still more preferably 5 μm or more and 150 μm orless, and particularly preferably 10 μm or more and 85 μm or less.

When the mean particle size of the powder 20 is 3 μm or more, the powder20 exhibits a higher fluidity and thus more easily forms the powderlayer 24, and the surface of the powder layer 24 can be more smooth.This configuration can improve shaping efficiency of thethree-dimensional shaped object 31 and also improve handleability anddimensional accuracy of the three-dimensional shaped object 31.

When the mean particle size of the powder 20 is 250 μm or less, thespace among the particles of the powder 20 in the powder layer 24 can bereduced. This configuration can reduce the porosity of thethree-dimensional shaped object 31, which can increase the strength ofthe three-dimensional shaped object 31. From the aforementionedviewpoints, the mean particle size of the powder 20 is preferably 3 μmor more and 250 μm or less to achieve both high dimensional accuracy andstrength.

The particle size distribution of the powder 20 may be selected asappropriate depending on the purpose, and thus is not limited to anyparticular value.

The angle of repose of the powder 20 is preferably 60 degrees orsmaller, more preferably 50 degrees or smaller, and still morepreferably 40 degrees or smaller. When the angle of repose of the powder20 is 60 degrees or smaller, particles of the powder 20 can be disposedefficiently and stably on desired positions. The angle of repose can bemeasured with, for example, a powder characteristics tester (PowderTester PT-N manufactured by Hosokawa Micron Corporation).

Shaping Liquid

Described next is the shaping liquid 28 used in the present embodiment.The shaping liquid 28 can be any type of liquid that dissolves thecoating layer of the powder 20 and then solidifies the coating layer.

The shaping liquid 28 can be prepared as appropriate depending on thematerial of the coating layer of the powder 20 used for the shaping. Forexample, the shaping liquid 28 contains a solvent that dissolves thecoating layer of the powder 20.

The solvent included in the shaping liquid 28 can be any type of solventthat can dissolve the coating layer of the powder 20, and thus is notlimited to any particular solvent. Examples of the solvent may includewater, alcohols such as ethanol, ethers, ketones, and other hydrophilicsolvents, aliphatic hydrocarbons, ether-based solvents such as glycolethers, ester-based solvents such as ethyl acetate, ketone-basedsolvents such as methyl ethyl ketone, and higher alcohols.

Among these solvents, a hydrophilic solvent is preferable and water ismore preferable in terms of environmental loads and dischargingstability of the shaping liquid 28. The hydrophilic solvent may be amixed solvent that contains water and other components such as alcohols.When the shaping liquid 28 contains a hydrophilic solvent, it ispreferable that the coating layer of the powder 20 is mainly made of awater-soluble organic material.

The hydrophilic solvent used for the shaping liquid 28 is, for example,water, alcohols such as ethanol, ethers, or ketones. The hydrophilicsolvent may be an organic solvent that contains other components thanwater, such as alcohols.

It is preferable that the shaping liquid 28 contains a cross-linkingagent that cross-links the material constituting the coating layer ofthe powder 20. The shaping liquid 28 may contain a solvent thatdissolves the coating layer of the powder 20, components that promotethe dissolution in the solvent, and stabilizers that keep thepreservation stability of the shaping liquid 28. The shaping liquid 28may contain still other components as necessary.

When the shaping liquid 28 contains a cross-linking agent, the shapingliquid 28 ejected onto the powder 20 dissolves the coating layer of thepowder 20 (or resins contained in the coating layer, for example) andcross-links the coating layer with the cross-linking agent contained inthe shaping liquid 28. Thereby, the coating layers of the particles ofthe powder 20 are combined with each other and thus the region on thepowder 20 to which the shaping liquid 28 is ejected solidifies.

The cross-linking agent contained in the shaping liquid 28 is notlimited to any particular agent, and can be any type of agent that cancross-link resins such as the organic material contained in the coatinglayer of the powder 20. The cross-linking agent may be selected asappropriate depending on the purpose. Examples of the cross-linkingagent may include metal salts, metal complexes, organozirconiumcompounds, organotitanium compounds, and chelating agents.

Examples of the organozirconium compounds may include zirconiumoxychloride, zirconium ammonium carbonate, and zirconium ammoniumlactate.

Examples of the organotitanium compounds may include titanium acylateand titanium alkoxide.

The metal salts are, for example, metal salts that ionize a divalent orhigher cationic metal in water. Specifically, metal salts may bezirconium oxychloride octahydrate (tetravalent), aluminum hydroxide(trivalent), magnesium hydroxide (divalent), ammonium salt of titaniumlactate (tetravalent), basic aluminum acetate (trivalent), ammonium saltof zirconium carbonate (tetravalent), or triethanolamine titanate(tetravalent).

The metal salts may be commercially available products. Examples of thecommercially available products may include zirconium oxychlorideoctahydrate (zirconium oxychloride manufactured by Daiichi KigensoKagaku Kogyo Co., Ltd.), aluminum hydroxide (manufactured by Wako PureChemical Industries, Ltd.), magnesium hydroxide (manufactured by WakoPure Chemical Industries, Ltd.), ammonium salt of titanium lactate(ORGATIX TC-300 manufactured by Matsumoto Fine Chemical Co., Ltd.),ammonium salt of zirconium lactate (ORGATIX ZC-300 manufactured byMatsumoto Fine Chemical Co., Ltd.), basic aluminum acetate (manufacturedby Wako Pure Chemical Industries, Ltd.), bis-vinyl sulfone compounds(VSB(K-FJC) manufactured by FUJIFILM Finechemicals Co., Ltd.), ammoniumsalt of zirconium carbonate (Zircosol AC-20 manufactured by DaiichiKigenso Kagaku Kogyo Co., Ltd.), triethanolamine titanate (ORGATIXTC-400 manufactured by Matsumoto Fine Chemical Co., Ltd.).

Among these commercially available products, ammonium salt of zirconiumcarbonate is preferred in terms of high strength of the resultingthree-dimensional shaped object 31.

The shaping liquid 28 may contain one type of cross-linking agent or aplurality of types of cross-linking agents. Among the aforementionedcompounds, metal salts are preferred for the use of the cross-linkingagent contained in the shaping liquid 28.

It is preferable that the shaping liquid 28 contains a surfactant. Usinga surfactant can adjust the surface tension of the shaping liquid 28.

The surfactant is, for example, an anionic surfactant or a nonionicsurfactant, or an amphoteric surfactant. It is preferable to select asurfactant that will not impair the dispersion stability with acombination of wetting agent and water-soluble organic solvent.

The viscosity of the shaping liquid 28 is not limited to any particularvalue, but, for example, the viscosity of the shaping liquid 28 at 25°C. is preferably 25 mPa·s or less, and more preferably 3 mPa·s or moreand 20 mPa·s or less. When the viscosity of the shaping liquid 28 at 25°C. is 25 mPa·s or less, the ejection unit 26 can stably eject theshaping liquid 28, which is preferable.

It is preferable that the viscosity change in the shaping liquid 28after standing for three days at 50° C. is less than 20%. When theviscosity change in the shaping liquid 28 is 20% or more, the ejectionunit 26 will unstably eject the shaping liquid 28 in some cases.

Described next is a hardware configuration of the information processingdevice 14 according to the present embodiment.

FIG. 13 is a diagram illustrating a hardware configuration of theinformation processing device 14. The information processing device 14includes a CPU 300, a read only memory (ROM) 302, a random access memory(RAM) 304, and an interface (I/F) 306. The CPU 300, the ROM 302, the RAM304, and the I/F 306 are connected with each other via a bus 308, andconstitute a hardware configuration using a typical computer.

The computer program for implementing the shaping processing executed bythe information processing device 14 according to the embodiment abovemay be embedded and provided in the ROM 302.

The computer program for implementing the shaping processing executed bythe information processing device 14 according to the embodiment abovemay be recorded and provided in a computer-readable recording mediumsuch as a compact disc read only memory (CD-ROM), a flexible disk (FD),a compact disc recordable (CD-R), and a digital versatile disc (DVD), asan installable or executable file.

The computer program for implementing the shaping processing executed bythe information processing device 14 according to the embodiment abovemay be stored in a computer connected to a network such as the Internetand downloaded via the network to provide the computer program.Furthermore, the computer program for implementing the shapingprocessing executed by the information processing device 14 according tothe embodiment above may be provided or distributed via a network suchas the Internet.

The computer program for implementing the shaping processing executed bythe information processing device 14 according to the embodiment abovehas a module configuration including the units described above. Asactual hardware, the units described above are loaded on the main memorywhen the CPU 300 reads out and executes the program from the ROM 302 orother storage media, and the units are generated on the main memory.

An embodiment provides an advantageous effect that strength loss in athree-dimensional shaped object can be reduced.

The above-described embodiments are illustrative and do not limit thepresent invention. Thus, numerous additional modifications andvariations are possible in light of the above teachings. For example, atleast one element of different illustrative and exemplary embodimentsherein may be combined with each other or substituted for each otherwithin the scope of this disclosure and appended claims. Further,features of components of the embodiments, such as the number, theposition, and the shape are not limited the embodiments and thus may bepreferably set. It is therefore to be understood that within the scopeof the appended claims, the disclosure of the present invention may bepracticed otherwise than as specifically described herein.

The method steps, processes, or operations described herein are not tobe construed as necessarily requiring their performance in theparticular order discussed or illustrated, unless specificallyidentified as an order of performance or clearly identified through thecontext. It is also to be understood that additional or alternativesteps may be employed.

Each of the functions of the described embodiments may be implemented byone or more processing circuits or circuitry. Processing circuitryincludes a programmed processor, as a processor includes circuitry. Aprocessing circuit also includes devices such as an application specificintegrated circuit (ASIC), digital signal processor (DSP), fieldprogrammable gate array (FPGA) and conventional circuit componentsarranged to perform the recited functions.

What is claimed is:
 1. A three-dimensional shaping apparatus comprising:a supply unit configured to supply powder; a leveling unit configured tolevel a surface of the supplied powder in a first direction to form apowder layer; an ejection unit configured to eject shaping liquid to atleast one position on a surface of the powder layer, the at least oneposition corresponding to a shaping target, to form at least one dot; acontrol unit configured to control the supply unit, the leveling unit,and the ejection unit to repeat a set of processes of supplying thepowder, forming the powder layer, and ejecting the shaping liquid toshape a three-dimensional shaped object corresponding to the shapingtarget; and a reception unit configured to receive a stop signalindicating a stop of operation and a resume signal indicating resumingof the operation, the control unit being configured to stop the set ofprocesses in response to reception of the stop signal, and in responseto reception of the resume signal after the reception of the stopsignal, control the supply unit, the leveling unit, and the ejectionunit to eject the shaping liquid onto at least a part of a dot region ona surface of an outermost powder layer, the dot region being formed byat least one dot formed at the outermost powder layer, and then resumethe set of processes.
 2. The three-dimensional shaping apparatusaccording to claim 1, wherein in response to the reception of the resumesignal after the reception of the stop signal, the control unit controlsthe supply unit, the leveling unit, and the ejection unit to eject theshaping liquid a plurality of times onto the at least a part of the dotregion on the surface of the outermost powder layer, the dot regionbeing formed by the at least one dot formed at the outermost powderlayer, and then resume the set of processes.
 3. The three-dimensionalshaping apparatus according to claim 1, wherein in response to thereception of the resume signal after the reception of the stop signal,the control unit controls the supply unit, the leveling unit, and theejection unit to eject an amount of the shaping liquid onto the at leasta part of the dot region formed by the at least one dot formed at theoutermost powder layer, the amount of the shaping liquid being such thata droplet of the shaping liquid having a thickness larger than zero andequal to or smaller than a thickness of the powder layer is made topresent on the surface of the outermost powder layer when the operationis resumed, and then resume the set of processes.
 4. Thethree-dimensional shaping apparatus according to claim 1, wherein inresponse to the reception of the resume signal after the reception ofthe stop signal, the control unit controls the supply unit, the levelingunit, and the ejection unit to eject an amount of the shaping liquidonto the at least a part of the dot region on the surface of theoutermost powder layer, the dot region being formed by the at least onedot formed at the outermost powder layer, the amount of the shapingliquid depending on a standby time from the reception of the stop signalto the reception of the resume signal, and then resume the set ofprocesses.
 5. The three-dimensional shaping apparatus according to claim1, wherein in response to the reception of the resume signal after thereception of the stop signal, the control unit controls the supply unit,the leveling unit, and the ejection unit to eject the shaping liquidonto a region inside an outline of the dot region on the surface of theoutermost powder layer, the dot region being formed by the at least onedot formed at the outermost powder layer, and then resume the set ofprocesses.
 6. A three-dimensional shaping method performed by athree-dimensional shaping apparatus including a supply unit configuredto supply powder, a leveling unit configured to level a surface of thesupplied powder in a first direction to form a powder layer, and anejection unit configured to eject shaping liquid to at least oneposition on a surface of the powder layer, the at least one positioncorresponding to a shaping target, to form at least one dot, thethree-dimensional shaping method comprising: controlling the supplyunit, the leveling unit, and the ejection unit to repeat a set ofprocesses of supplying the powder, forming the powder layer, andejecting the shaping liquid to shape a three-dimensional shaped objectcorresponding to the shaping target; and receiving a stop signalindicating a stop of operation and a resume signal indicating resumingof the operation, wherein the controlling includes: stopping the set ofprocesses in response to reception of the stop signal, and controlling,in response to reception of the resume signal after the reception of thestop signal, the supply unit, the leveling unit, and the ejection unitto eject the shaping liquid onto at least a part of a dot region on asurface of an outermost powder layer, the dot region being formed by atleast one dot formed at the outermost powder layer, and then resume theset of processes.
 7. An information processing device configured tocontrol a shaping device including a supply unit configured to supplypowder, a leveling unit configured to level a surface of the suppliedpowder in a first direction to form a powder layer, and an ejection unitconfigured to eject shaping liquid to at least one position on a surfaceof the powder layer, the at least one position corresponding to ashaping target, to form at least one dot, the information processingdevice comprising: a control unit configured to control the supply unit,the leveling unit, and the ejection unit to repeat a set of processes ofsupplying the powder, forming the powder layer, and ejecting the shapingliquid to shape a three-dimensional shaped object corresponding to theshaping target; and a reception unit configured to receive a stop signalindicating a stop of operation and a resume signal indicating resumingof the operation, the control unit being configured to stop the set ofprocesses in response to reception of the stop signal, and in responseto reception of the resume signal after the reception of the stopsignal, control the supply unit, the leveling unit, and the ejectionunit to eject the shaping liquid onto at least a part of a dot region ona surface of an outermost powder layer, the dot region being formed byat least one dot formed at the outermost powder layer, and then resumethe set of processes.